Efficient Paradigm to Measure Street-Crossing Onset Time of Pedestrians in Video-Based Interactions with Vehicles

With self-driving vehicles (SDVs), pedestrians can no longer rely on a human driver. Previous research suggests that pedestrians may benefit from an external Human–Machine Interface (eHMI) displaying information to surrounding traffic participants. This paper introduces a natural methodology to compare eHMI concepts from a pedestrian’s viewpoint. To measure eHMI effects on traffic flow, previous video-based studies instructed participants to indicate their crossing decision with interfering data collection devices, such as pressing a button or slider. We developed a quantifiable concept that allows participants to naturally step off a sidewalk to cross the street. Hidden force-sensitive resistor sensors recorded their crossing onset time (COT) in response to real-life videos of approaching vehicles in an immersive crosswalk simulation environment. We validated our method with an initial study of N = 34 pedestrians by showing (1) that it is able to detect significant eHMI effects on COT as well as subjective measures of perceived safety and user experience. The approach is further validated by (2) replicating the findings of a test track study and (3) participants’ reports that it felt natural to take a step forward to indicate their street crossing decision. We discuss the benefits and limitations of our method with regard to related approaches. Document type: Articl

Pedestrian Models for Autonomous Driving Part II: High-Level Models of Human Behavior

Abstract—Autonomous vehicles (AVs) must share space with pedestrians, both in carriageway cases such as cars at pedestrian crossings and off-carriageway cases such as delivery vehicles navigating through crowds on pedestrianized high-streets. Unlike static obstacles, pedestrians are active agents with complex, inter- active motions. Planning AV actions in the presence of pedestrians thus requires modelling of their probable future behaviour as well as detecting and tracking them. This narrative review article is Part II of a pair, together surveying the current technology stack involved in this process, organising recent research into a hierarchical taxonomy ranging from low-level image detection to high-level psychological models, from the perspective of an AV designer. This self-contained Part II covers the higher levels of this stack, consisting of models of pedestrian behaviour, from prediction of individual pedestrians’ likely destinations and paths, to game-theoretic models of interactions between pedestrians and autonomous vehicles. This survey clearly shows that, although there are good models for optimal walking behaviour, high-level psychological and social modelling of pedestrian behaviour still remains an open research question that requires many conceptual issues to be clarified. Early work has been done on descriptive and qualitative models of behaviour, but much work is still needed to translate them into quantitative algorithms for practical AV control

Standardized Test Procedure for External Human–Machine Interfaces of Automated Vehicles

Research on external human&ndash machine interfaces (eHMIs) has recently become a major area of interest in the field of human factors research on automated driving. The broad variety of methodological approaches renders the current state of research inconclusive and comparisons between interface designs impossible. To date, there are no standardized test procedures to evaluate and compare different design variants of eHMIs with each other and with interactions without eHMIs. This article presents a standardized test procedure that enables the effective usability evaluation of eHMI design solutions. First, the test procedure provides a methodological approach to deduce relevant use cases for the evaluation of an eHMI. In addition, we define specific usability requirements that must be fulfilled by an eHMI to be effective, efficient, and satisfying. To prove whether an eHMI meets the defined requirements, we have developed a test protocol for the empirical evaluation of an eHMI with a participant study. The article elucidates underlying considerations and details of the test protocol that serves as framework to measure the behavior and subjective evaluations of non-automated road users when interacting with automated vehicles in an experimental setting. The standardized test procedure provides a useful framework for researchers and practitioners. Document type: Articl

차량용 헤드업 디스플레이 설계에 관한 인간공학 연구

학위논문 (박사) -- 서울대학교 대학원 : 공과대학 산업공학과, 2020. 8. 박우진.Head-up display (HUD) systems were introduced into the automobile industry as a means for improving driving safety. They superimpose safety-critical information on top of the drivers forward field of view and thereby help drivers keep their eyes forward while driving. Since the first introduction about three decades ago, automotive HUDs have been available in various commercial vehicles. Despite the long history and potential benefits of automotive HUDs, however, the design of useful automotive HUDs remains a challenging problem. In an effort to contribute to the design of useful automotive HUDs, this doctoral dissertation research conducted four studies. In Study 1, the functional requirements of automotive HUDs were investigated by reviewing the major automakers' automotive HUD products, academic research studies that proposed various automotive HUD functions, and previous research studies that surveyed drivers HUD information needs. The review results indicated that: 1) the existing commercial HUDs perform largely the same functions as the conventional in-vehicle displays, 2) past research studies proposed various HUD functions for improving driver situation awareness and driving safety, 3) autonomous driving and other new technologies are giving rise to new HUD information, and 4) little research is currently available on HUD users perceived information needs. Based on the review results, this study provides insights into the functional requirements of automotive HUDs and also suggests some future research directions for automotive HUD design. In Study 2, the interface design of automotive HUDs for communicating safety-related information was examined by reviewing the existing commercial HUDs and display concepts proposed by academic research studies. Each display was analyzed in terms of its functions, behaviors and structure. Also, related human factors display design principles, and, empirical findings on the effects of interface design decisions were reviewed when information was available. The results indicated that: 1) information characteristics suitable for the contact-analog and unregistered display formats, respectively, are still largely unknown, 2) new types of displays could be developed by combining or mixing existing displays or display elements at both the information and interface element levels, and 3) the human factors display principles need to be used properly according to the situation and only to the extent that the resulting display respects the limitations of the human information processing, and achieving balance among the principles is important to an effective design. On the basis of the review results, this review suggests design possibilities and future research directions on the interface design of safety-related automotive HUD systems. In Study 3, automotive HUD-based take-over request (TOR) displays were developed and evaluated in terms of drivers take-over performance and visual scanning behavior in a highly automated driving situation. Four different types of TOR displays were comparatively evaluated through a driving simulator study - they were: Baseline (an auditory beeping alert), Mini-map, Arrow, and Mini-map-and-Arrow. Baseline simply alerts an imminent take-over, and was always included when the other three displays were provided. Mini-map provides situational information. Arrow presents the action direction information for the take-over. Mini-map-and-Arrow provides the action direction together with the relevant situational information. This study also investigated the relationship between drivers initial trust in the TOR displays and take-over and visual scanning behavior. The results indicated that providing a combination of machine-made decision and situational information, such as Mini-map-and-Arrow, yielded the best results overall in the take-over scenario. Also, drivers initial trust in the TOR displays was found to have significant associations with the take-over and visual behavior of drivers. The higher trust group primarily relied on the proposed TOR displays, while the lower trust group tended to more check the situational information through the traditional displays, such as side-view or rear-view mirrors. In Study 4, the effect of interactive HUD imagery location on driving and secondary task performance, driver distraction, preference, and workload associated with use of scrolling list while driving were investigated. A total of nine HUD imagery locations of full-windshield were examined through a driving simulator study. The results indicated the HUD imagery location affected all the dependent measures, that is, driving and task performance, drivers visual distraction, preference and workload. Considering both objective and subjective evaluations, interactive HUDs should be placed near the driver's line of sight, especially near the left-bottom on the windshield.자동차 헤드업 디스플레이는 차내 디스플레이 중 하나로 운전자에게 필요한 정보를 전방에 표시함으로써, 운전자가 운전을 하는 동안 전방으로 시선을 유지할 수 있게 도와준다. 이를 통해 운전자의 주의 분산을 줄이고, 안전을 향상시키는데 도움이 될 수 있다. 자동차 헤드업 디스플레이 시스템은 약 30년 전 운전자의 안전을 향상시키기 위한 수단으로 자동차 산업에 처음 도입된 이래로 현재까지 다양한 상용차에서 사용되고 있다. 안전과 편의 측면에서 자동차 헤드업 디스플레이의 사용은 점점 더 증가할 것으로 예상된다. 그러나 이러한 자동차 헤드업 디스플레이의 잠재적 이점과 발전 가능성에도 불구하고, 유용한 자동차 헤드업 디스플레이를 설계하는 것은 여전히 어려운 문제이다. 이에 본 연구는 이러한 문제를 해결하고, 궁극적으로 유용한 자동차 헤드업 디스플레이 설계에 기여하고자 총 4가지 연구를 수행하였다. 첫 번째 연구는 자동차 헤드업 디스플레이의 기능 요구 사항과 관련된 것으로서, 헤드업 디스플레이 시스템을 통해 어떤 정보를 제공할 것인가에 대한 답을 구하고자 하였다. 이에 주요 자동차 제조업체들의 헤드업 디스플레이 제품들과, 자동차 헤드업 디스플레이의 다양한 기능들을 제안한 학술 연구, 그리고 운전자의 정보 요구 사항들을 체계적 문헌 고찰 방법론을 통해 포괄적으로 조사하였다. 자동차 헤드업 디스플레이의 기능적 요구 사항에 대하여 개발자, 연구자, 사용자 측면을 모두 고려한 통합된 지식을 전달하고, 이를 통해 자동차 헤드업 디스플레이의 기능 요구 사항에 대한 향후 연구 방향을 제시하였다. 두 번째 연구는 안전 관련 정보를 제공하는 자동차 헤드업 디스플레이의 인터페이스 설계와 관련된 것으로, 헤드업 디스플레이 시스템을 통해 안전 관련 정보를 어떻게 제공할 것인가에 대한 답을 구하고자 하였다. 실제 자동차들의 헤드업 디스플레이 시스템에서는 어떤 디스플레이 컨셉들이 사용되었는지, 그리고 학계에서 제안된 디스플레이 컨셉들에는 어떤 것들이 있는지 체계적 문헌 고찰 방법론을 통해 검토하였다. 검토된 결과는 각 디스플레이의 기능과 구조, 그리고 작동 방식에 따라 정리되었고, 관련된 인간공학적 디스플레이 설계 원칙과 실험적 연구 결과들을 함께 검토하였다. 검토된 결과를 바탕으로 안전 관련 정보를 제공하는 자동차 헤드업 디스플레이의 인터페이스 설계에 대한 향후 연구 방향을 제시하였다. 세 번째 연구는 자동차 헤드업 디스플레이 기반의 제어권 전환 관련 인터페이스 설계와 평가에 관한 것이다. 제어권 전환이란, 자율주행 상태에서 운전자가 직접 운전을 하는 수동 운전 상태로 전환이 되는 것을 의미한다. 따라서 갑작스런 제어권 전환 요청이 발생하는 경우, 운전자가 안전하게 대처하기 위해서는 빠른 상황 파악과 의사 결정이 필요하게 되고, 이를 효과적으로 도와주기 위한 인터페이스 설계에 대해 연구할 필요성이 있다. 이에 본 연구에서는 자동차 헤드업 디스플레이 기반의 총 4개의 제어권 전환 관련 디스플레이(기준 디스플레이, 미니맵 디스플레이, 화살표 디스플레이, 미니맵과 화살표 디스플레이)를 제안하였고, 제안된 디스플레이 대안들은 주행 시뮬레이터 실험을 통해 제어권 전환 수행 능력과 안구의 움직임 패턴, 그리고 사용자의 주관적 평가 측면에서 평가되었다. 또한 제안된 디스플레이 대안들에 대해 운전자들의 초기 신뢰도 값을 측정하여 각 디스플레이에 따른 운전자들의 평균 신뢰도 점수에 따라 제어권 전환 수행 능력과 안구의 움직임 패턴, 그리고 주관적 평가가 어떻게 달라지는지 분석하였다. 실험 결과, 제어권 전환 상황에서 자동화된 시스템이 제안하는 정보와 그와 관련된 주변 상황 정보를 함께 제시해 주는 디스플레이가 가장 좋은 결과를 보여주었다. 또한 각 디스플레이에 대한 운전자의 초기 신뢰도 점수는 디스플레이의 실제 사용 행태와 밀접한 관련이 있음을 알 수 있었다. 신뢰도 점수에 따라 신뢰도가 높은 그룹과 낮은 그룹으로 분류되었고, 신뢰도가 높은 그룹은 제안된 디스플레이들이 보여주는 정보를 주로 믿고 따르는 경향이 있었던 반면, 신뢰도가 낮은 그룹은 룸 미러나 사이드 미러를 통해 주변 상황 정보를 더 확인 하는 경향을 보였다. 네 번째 연구는 전면 유리창에서의 인터랙티브 헤드업 디스플레이의 최적 위치를 결정하는 것으로서 주행 시뮬레이터 실험을 통해 디스플레이의 위치에 따라 운전자의 주행 수행 능력, 인터랙티브 디스플레이 조작 관련 과업 수행 능력, 시각적 주의 분산, 선호도, 그리고 작업 부하가 평가되었다. 헤드업 디스플레이의 위치는 전면 유리창에서 일정한 간격으로 총 9개의 위치가 고려되었다. 본 연구에서 활용된 인터랙티브 디스플레이는 음악 선택을 위한 스크롤 방식의 단일 디스플레이였고, 운전대에 장착된 버튼을 통해 디스플레이를 조작하였다. 실험 결과, 인터랙티브 헤드업 디스플레이의 위치가 모든 평가 척도, 즉 주행 수행 능력, 디스플레이 조작 과업 수행 능력, 시각적 주의 분산, 선호도, 그리고 작업 부하에 영향을 미침을 알 수 있었다. 모든 평가 지표를 고려했을 때, 인터랙티브 헤드업 디스플레이의 위치는 운전자가 똑바로 전방을 바라볼 때의 시야 구간, 즉 전면 유리창에서의 왼쪽 아래 부근이 가장 최적인 것으로 나타났다.Abstract i Contents v List of Tables ix List of Figures x Chapter 1 Introduction 1 1.1 Research Background 1 1.2 Research Objectives and Questions 8 1.3 Structure of the Thesis 11 Chapter 2 Functional Requirements of Automotive Head-Up Displays: A Systematic Review of Literature from 1994 to Present 13 2.1 Introduction 13 2.2 Method 15 2.3 Results 17 2.3.1 Information Types Displayed by Existing Commercial Automotive HUD Systems 17 2.3.2 Information Types Previously Suggested for Automotive HUDs by Research Studies 28 2.3.3 Information Types Required by Drivers (users) for Automotive HUDs and Their Relative Importance 35 2.4 Discussion 39 2.4.1 Information Types Displayed by Existing Commercial Automotive HUD Systems 39 2.4.2 Information Types Previously Suggested for Automotive HUDs by Research Studies 44 2.4.3 Information Types Required by Drivers (users) for Automotive HUDs and Their Relative Importance 48 Chapter 3 A Literature Review on Interface Design of Automotive Head-Up Displays for Communicating Safety-Related Information 50 3.1 Introduction 50 3.2 Method 52 3.3 Results 55 3.3.1 Commercial Automotive HUDs Presenting Safety-Related Information 55 3.3.2 Safety-Related HUDs Proposed by Academic Research 58 3.4 Discussion 74 Chapter 4 Development and Evaluation of Automotive Head-Up Displays for Take-Over Requests (TORs) in Highly Automated Vehicles 78 4.1 Introduction 78 4.2 Method 82 4.2.1 Participants 82 4.2.2 Apparatus 82 4.2.3 Automotive HUD-based TOR Displays 83 4.2.4 Driving Scenario 86 4.2.5 Experimental Design and Procedure 87 4.2.6 Experiment Variables 88 4.2.7 Statistical Analyses 91 4.3 Results 93 4.3.1 Comparison of the Proposed TOR Displays 93 4.3.2 Characteristics of Drivers Initial Trust in the four TOR Displays 102 4.3.3 Relationship between Drivers Initial Trust and Take-over and Visual Behavior 104 4.4 Discussion 113 4.4.1 Comparison of the Proposed TOR Displays 113 4.4.2 Characteristics of Drivers Initial Trust in the four TOR Displays 116 4.4.3 Relationship between Drivers Initial Trust and Take-over and Visual Behavior 117 4.5 Conclusion 119 Chapter 5 Human Factors Evaluation of Display Locations of an Interactive Scrolling List in a Full-windshield Automotive Head-Up Display System 121 5.1 Introduction 121 5.2 Method 122 5.2.1 Participants 122 5.2.2 Apparatus 123 5.2.3 Experimental Tasks and Driving Scenario 123 5.2.4 Experiment Variables 124 5.2.5 Experimental Design and Procedure 126 5.2.6 Statistical Analyses 126 5.3 Results 127 5.4 Discussion 133 5.5 Conclusion 135 Chapter 6 Conclusion 137 6.1 Summary and Implications 137 6.2 Future Research Directions 139 Bibliography 143 Apeendix A. Display Layouts of Some Commercial HUD Systems Appendix B. Safety-related Displays Provided by the Existing Commercial HUD Systems Appendix C. Safety-related HUD displays Proposed by Academic Research 국문초록 187Docto

Vulnerable road users and the coming wave of automated vehicles: Expert perspectives

Automated driving research over the past decades has mostly focused on highway environments. Recent technological developments have drawn researchers and manufacturers to look ahead at introducing automated driving in cities. The current position paper examines this challenge from the viewpoint of scientific experts. Sixteen Human Factors researchers were interviewed about their personal perspectives on automated vehicles (AVs) and the interaction with VRUs in the future urban environment. Aspects such as smart infrastructure, external human-machine interfaces (eHMIs), and the potential of augmented reality (AR) were addressed during the interviews. The interviews showed that the researchers believed that fully autonomous vehicles will not be introduced in the coming decades and that intermediate levels of automation, specific AV services, or shared control will be used instead. The researchers foresaw a large role of smart infrastructure and expressed a need for AV-VRU segregation, but were concerned about corresponding costs and maintenance requirements. The majority indicated that eHMIs will enhance future AV-VRU interaction, but they noted that implicit communication will remain dominant and advised against text-based and instructive eHMIs. AR was commended for its potential in assisting VRUs, but given the technological challenges, its use, for the time being, was believed to be limited to scientific experiments. The present expert perspectives may be instrumental to various stakeholders and researchers concerned with the relationship between VRUs and AVs in future urban traffic

Erfahrungseffekte von Fußgänger:innen bei der Interaktion mit automatisierten Pkw : Ein Untersuchungskonzept

Dieser Beitrag für die DoktorandInnenwerkstatt zeigt ein Konzept zur Untersuchung des Verhaltens von Fußgänger:innen bei der Interaktion mit automatisierten Pkw und der Bildung von Verhaltensanpassungen mit steigender Interaktionserfahrung des Menschen auf